In order to allow a general customer to judge in advance whether a hairstyle will suit the customer without actually changing the current hairstyle, a hairstyle simulation image is formed by combining the face image of the customer and a hair image of the hairstyle designated by the customer. Conventionally, to form such a hairstyle simulation image, an operator manually adjusts the sizes and the positions of the face and hair images to be superposed.
However, with such a method, it is not possible to provide the hairstyle simulation image to the customer in a short period of time, so that in practice the customer cannot try different hairstyles at a hair salon or the like. In addition, it is difficult to deal with all requests to form hairstyle simulation images when the number of the requests is large.
In view of the above, a method has been proposed which includes: automatically extracting a facial region from a face image; determining the maximum width of the outline of the facial region, the maximum width being used as the facial width of the face image; and automatically fitting a hair image to the face image by matching the facial widths of the hair and face images with each other (Patent Document 1). In this method, the facial width is used as the basis of the fitting process. However, the facial width of an image of a single person can differ depending on whether or not the hair partially covers the face. Therefore, an unnatural hairstyle simulation image can be formed in which the hair and face images do not fit well with each other.
[Patent Document 1] JP-A-1997-131252.